program class1q2a; uses wincrt;
const G = 6.64E-11;
var m1, m2, r, F : real;
begin
  write('m1: ');
  readln(m1);
  write('m2: ');
  readln(m2);
  write('r: ');
  readln(r);
  writeln;
  F := G*m1*m2/(r*r);
  writeln('The force between two objects is ',F,' N.')
end.
